In a conventional pneumatic tire, such as a conventional high-performance tire, a tread pattern is generally formed by combining circumferential grooves extending in the circumferential direction of the tire with a plurality of grooves inclined relative to the circumferential direction. The combination of grooves forms a plurality of tread blocks along the radially outer surface of tire. If the inclined grooves do not extend completely across the equatorial plane of the tire, a central rib may also be formed in the tread.
Certain conventional vehicles can be used both for commuting over paved highways and, also, for recreational use in off-highway situations. Such vehicles often take the form of pick-up trucks or small general purpose motor vehicles with four wheel drive capability. Such vehicles present a particular challenge to a tire designer because the performance characteristics desired for highway use usually require tradeoffs with the performance characteristics for off-road use. For example, some of these tradeoffs may be mud traction versus treadwear, off-road handling versus on-road handling, and wet traction versus dry traction. Furthermore, when an on/off road, all purpose vehicle is used for commuting on paved streets, it is seldom loaded to its full weight capacity. However, when the same vehicle is packed with recreational equipment for off-road use, the tires may be subjected to much greater mechanical loads. It would be desirable for a tire to have the capacity to provide a combination of good characteristics, such adequate treadwear, mud traction, sand traction, on road handling, off road handling, wet traction, and dry traction.